Methods for automated assembly of roof panel structures

ABSTRACT

A portable roof panel structure assembly mechanism that may be transported to a construction site and that is used to automatically assemble roof panel structures at the site. The assembly mechanism includes a purlin feeder, subpurlin clamping mechanisms and feeders, and a diaphragm feeder. The purlin feeder lifts a purlin into position, and advances the purlin into an assembly station. The subpurlin feeders insert a subpurlin into each of a plurality of subpurlin clamping mechanisms, and the clamping mechanisms advance into the assembly station and hold the subpurlins against the section of the purlin that has been advanced. The diaphragm feeder places a diaphragm onto the subpurlins and the purlin at the assembly station. The components are attached by automatic nailers.

REFERENCE TO RELATED APPLICATIONS

[0001] The present invention is related to U.S. patent applicationsentitled “APPARATUS FOR AND METHOD OF CONSTRUCTING PANELIZED ROOFSTRUCTURES” (Attorney Docket No. 29003-11010) and “APPARATUS FORASSEMBLY OF ROOF PANEL STRUCTURES” (Attorney Docket No. 29003-11030),”having a common inventor, filed concurrently herewith, and herebyincorporated by reference in their entireties.

FIELD OF THE INVENTION

[0002] The present invention relates generally to roof structures, andmore particularly to the fabrication of panelized roof structures.

BACKGROUND OF THE INVENTION

[0003] Roofs for contemporary buildings, particularly light industrialbuildings having rectangular-shaped roofing, typically are formed fromroof panel structures that are attached to main supporting beams. Ingeneral, a roof panel structure includes a purlin (i.e., a major beam)that, when installed, is attached orthogonally to the main supportingbeams of the structure, subpurlins (i.e., minor beams such as lumberstiffeners) that are attached orthogonally to the purlin, and diaphragms(e.g., wood structural panels) that are nailed to the subpurlins and thepurlin for structural and shear support. Completed roof panel structuresmay be 25 to 80 feet in length or even longer, and are often lifted toand placed on the main supporting beams by a crane or forklift. Once inplace, the roof panel structures are typically nailed to the mainsupporting beams and adjacent roof panel structures.

[0004] In practice, each of the components of the roof panel structuresis brought to a site and the roof panel structures are assembled byhand. Some manufacturers preassemble the subpurlins and the diaphragmsoffsite (typically in four-foot segments, but sometimes in eight-footsegments), and use the preassembled subpurlins and diaphragms at thesite to form the roof panel structures. Even if the preassemblies areused, however, many carpenters and other construction workers arerequired in the roofing area to complete assembly and/or installation ofthe roof panel structures. Thus, although present roof panel structureswork well for their intended purpose, their assembly can be timeconsuming and expensive. Moreover, the amount of labor involved mayintroduce errors into assembly, which may cause additional expenses oftime, labor, and materials. In addition, the labor involved may besomewhat dangerous and/or strenuous, and very often requires young,attentive workers.

SUMMARY OF THE INVENTION

[0005] The present invention provides a portable roof panel structureassembly mechanism that may be transported to a construction site andthat is used to automatically assemble roof panel structures at thesite. The roof panel structure assembly mechanism includes a purlinfeeder, subpurlin clamping mechanisms and feeders, and a diaphragmfeeder. The purlin feeder advances a purlin into an assembly station.The subpurlin feeders insert a subpurlin into each of a plurality ofsubpurlin clamping mechanisms, and the clamping mechanisms advance intothe assembly station and hold the subpurlins against the section of thepurlin that has been already advanced into the assembly station. Thediaphragm feeder places a diaphragm onto the subpurlins and the purlinat the assembly station. The components are then ready for attachment.

[0006] In accordance with one aspect of the present invention, one ormore automatic nailers (e.g., nailing guns) may be used to attach thediaphragm, the subpurlins, and the purlin at the assembly station. Theautomatic nailers may be provided, for example, on a nailing carriagethat moves with a lifting carriage that is used to deliver and place thediaphragm over the subpurlin and the purlin. If multiple nailing gunsare used, particular guns may be fired according to the position of thegun and the length and/or width of the diaphragm. In accordance with anaspect of the present invention, once the subpurlins, purlin, anddiaphragm are in place, the nailing of the components together occursautomatically.

[0007] In accordance with another aspect of the present invention, thepurlin feeder includes a height adjustment mechanism that permits thetop level of a purlin on the feeder to be adjusted to a preselectedheight, regardless of the height of the purlin. After the purlin hasbeen raised or lowered to the preselected height, the purlin is advancedinto the assembly station. Subpurlins and a diaphragm are moved againstthe purlin in the assembly station, and are attached to the purlin, suchas by the automatic nailers on the nailing carriage. The purlin is thenindexed the width of the diaphragm, and the next subpurlins anddiaphragm are placed against the new section of the purlin, and may beattached to the purlin at the assembly station (e.g., by the nailingcarriage).

[0008] The end of the purlin having subpurlins and diaphragm(s) attachedthereto advances into an exit station. The exit station includes asupport for the purlin, which is adjustable for height similar to, orthe same as, the lifting mechanism for the purlin feeder. A secondsupport is provided for the side of the assembled roof panel structurehaving the subpurlins and diaphragms (i.e., opposite the purlin). Inaccordance with another aspect of the present invention, a fork lift isprovided with tines that are specially configured to lift the roof panelstructure from the exit station.

[0009] In accordance with still another aspect of the present invention,the subpurlin clamping mechanisms are mounted on a carriage thatadvances the clamping mechanisms and the subpurlins into the assemblystation. The carriage may, for example, include a clamping mechanism foreach subpurlin. Feeders are provided to supply subpurlins to theclamping mechanisms. According to one aspect of the present invention, aseparate subpurlin feeder is provided for each subpurlin clampingmechanism. The subpurlin feeders may be, for example, vertical magazinesor indexing units that drop a bottom subpurlin into a subpurlin clampingmechanism while a penultimate subpurlin is supported.

[0010] The subpurlin clamping mechanisms may include clamps or pinchersthat close on opposite sides of the subpurlin and thereby position asubpurlin in a subpurlin clamping mechanism. The clamps may includesensors for determining or confirming the thickness of a subpurlin in asubpurlin clamping mechanism.

[0011] A rod or other device may be used to press a subpurlin againstthe purlin after the carriage has advanced the subpurlins into theassembly station. A sensor may be used to determine the length of thestroke of the rod so that the subpurlin length may be detected orconfirmed.

[0012] If the subpurlin includes brackets that are configured to extendover the purlin, in accordance with an aspect of the present invention,the carriage, the subpurlins, or the clamping mechanisms may be liftedas the brackets and subpurlins approach the purlin, so that the bracketsare raised above a top edge of the purlin. This feature assures that thebrackets clear the top edge of the purlin, instead of hitting the purlinas the brackets are advanced. The subpurlins, clamping mechanisms, orcarriage may then be lowered, so that the brackets rest on top of thepurlin.

[0013] In accordance with one aspect of the present invention, thediaphragm feeder includes a diaphragm carriage. In one embodiment, thediaphragm carriage includes the nailing carriage and a lifting carriagefor lifting and placing the diaphragm onto the subpurlin and/or purlin.This lifting carriage may include some form of device for grasping adiaphragm, for example, suction cups.

[0014] The lifting carriage may lift the diaphragm from a pile ofdiaphragms. In accordance with another aspect of the present invention,the pile of diaphragms may be provided on a lift designed such that atop diaphragm stays at substantially the same height as diaphragms areremoved.

[0015] In accordance with an aspect of the present invention, thelifting carriage is movable relative to the diaphragm carriage, and may,for example, be mounted on a diaphragm carriage for rotational and threedimensional movement. Sensors may be provided for aiding in properalignment of a diaphragm held by the lifting carriage before thediaphragm is placed on the subpurlins and purlin.

[0016] The nailing carriage may be separate from the diaphragm carriage,or may be mounted thereon, for example, on a lower portion of thediaphragm carriage. In accordance with one aspect of the presentinvention, a diaphragm is lowered into place in the assembly station bythe lifting carriage, and the automatic nailers nail the diaphragm tothe purlin and/or subpurlin before the holding device releases thediaphragm. The holding mechanism is then released and the liftingcarriage is retracted. The nailing carriage may then index so that theautomatic nailers may nail the diaphragm at other locations. Thisprocess may be continued until nailing is complete. The nailing processmay require turning some automatic nailers on in some locations, and offin others, depending upon the configuration of the roof panel structureand the location of the automatic nailers. To aid in aligning theautomatic nailers in the proper location, the diaphragm carriage isconfigured to provide lateral movement of the nailing carriage, such asin the x- and y-directions.

[0017] The system may include a computer that permits the lengths and/orwidths of the purlin, subpurlin, and diaphragms to be entered, so thatthe entire process is automatic once started. The sensors ensure thatthe appropriate size of subpurlins and diaphragms are in place andproperly aligned, and serve as checks on the automated assembly.

[0018] The roof panel structure assembly mechanism of the presentinvention may be operated by a minimal number of workers, but yetgenerates multiple roof panel structures in a fraction of the time ofconventional, manual assembly. In addition, workers that are lessmobile, and that are not capable of strenuous activity may be used tooperate the roof panel structure assembly mechanism. The roof panelstructure assembly mechanism is fully portable, so it may be deliveredto a site where assembly is needed.

[0019] Other advantages will become apparent from the following detaileddescription when taken in conjunction with the drawings, in which:

BRIEF DESCRIPTION OF THE DRAWINGS

[0020]FIG. 1 is a side perspective view of a mechanism for assemblingroof panel structures in accordance with one aspect of the presentinvention, with parts removed to show detail;

[0021]FIG. 2 is an exploded perspective view a roof panel structure,used to show one typical construction of such a structure;

[0022]FIG. 3 is a side perspective view of a purlin feeder for the roofpanel structure assembly mechanism of FIG. 1;

[0023]FIG. 4 is a side perspective view of a lifting mechanism for thepurlin feeder of FIG. 3;

[0024]FIG. 5 is a top view of a portion of the purlin feeder of FIG. 3;

[0025]FIG. 6 is a side view of a portion of the purlin feeder of FIG. 3,with a purlin shown in a lowered position;

[0026]FIG. 7 is a side view of a portion of the purlin feeder of FIG. 3,similar to FIG. 6, with a purlin shown in a higher position;

[0027]FIG. 8 is a side perspective view of the roof panel structureassembly mechanism of FIG. 1, with parts removed for detail, and showingan assembled roof panel structure in an exit station, the assembled roofpanel structure being shown in phantom;

[0028]FIG. 9 shows a side perspective view, similar to FIG. 8, with theroof panel structure not being in phantom;

[0029]FIG. 10 is a side perspective view of a roof panel structure inthe exit station of FIG. 8, with a forklift shown preparing to removethe roof panel structure from the exit station;

[0030] FIGS. 11-13 are side views showing various stages of a forkliftremoving the roof panel structure of FIG. 10 from the exit station;

[0031]FIG. 14 is a side perspective view of a subpurlin station and adiaphragm station for the roof panel structure assembly mechanism ofFIG. 1;

[0032]FIG. 15 is a side perspective view showing a portion of thesubpurlin station of FIG. 14;

[0033]FIG. 16 is a rear view of the subpurlin station FIG. 15;

[0034]FIG. 17 is a rear view of the subpurlin station FIG. 15, similarto FIG. 16, with subpurlin feeders being closed against subpurlins inthe subpurlin feeders;

[0035]FIG. 18 is a side perspective detail view of a release mechanismfor the subpurlin feeders of FIG. 17;

[0036]FIG. 19 is a bottom view of the subpurlin feeders of FIG. 17;

[0037]FIG. 20 is a bottom view of the subpurlin feeders of FIG. 17,similar to FIG. 19, with arms of the subpurlin feeders open so thatbottom subpurlins may be released;

[0038]FIG. 21 is a rear view, similar to FIG. 17, showing the bottomsubpurlins dropped from the subpurlin feeder and into subpurlin clampingmechanisms;

[0039]FIG. 22 is a side perspective detail view of the bottom subpurlinsbeing dropped as in FIG. 21;

[0040]FIG. 23 is a side perspective view of a subpurlin carriage for thesubpurlin clamping mechanisms of FIG. 21;

[0041]FIG. 24 is a top view of the subpurlin clamping mechanisms of FIG.23;

[0042]FIG. 25 is a side perspective detail view of a pinching mechanismfor use in the subpurlin clamping mechanisms of FIG. 23;

[0043]FIG. 26 is a side perspective view of a pinching mechanism for usein the subpurlin clamping mechanisms of FIG. 23, similar to FIG. 25,showing the pinching mechanisms closed;

[0044]FIG. 27 is a side view of a push bar system for use on the leadingend of the subpurlin carriage of FIG. 23;

[0045]FIG. 28 is a side view, similar to FIG. 27, showing the push barengaging a purlin;

[0046]FIG. 29 is a side perspective view of a front end of the subpurlincarriage;

[0047]FIG. 30 is a diagrammatic view of a drive system for the subpurlincarriage;

[0048]FIG. 31 is a diagrammatic side view showing the subpurlin carriagepositioned below the subpurlin feeders;

[0049]FIG. 32 is a diagrammatic side view, similar to FIG. 31, showingthe subpurlin carriage advancing into an assembly station;

[0050]FIG. 33 is a diagrammatic side view, similar to FIG. 32, showingthe subpurlin carriage further advanced into the assembly station;

[0051]FIG. 34 is a side detail view showing the subpurlin carriage as itapproaches a purlin in the assembly station, with a front end of thesubpurlins lifted;

[0052]FIG. 35 is a side detail view, similar to FIG. 34, showing thesubpurlins being lowered against a purlin in the assembly station;

[0053]FIG. 36 is a top view of the subpurlin carriage in the positionshown in FIG. 35;

[0054]FIG. 37 is a diagrammatic side view, similar to FIG. 32, showingthe subpurlin carriage in the position in FIG. 35;

[0055]FIG. 38 is a diagrammatic side view, similar to FIG. 37, showingthe subpurlin carriage fully retracted back to underneath the subpurlinfeeders;

[0056]FIG. 39 is a diagrammatic side view, similar to FIG. 38, showing abeginning stage of movement of a diaphragm lift;

[0057]FIG. 40 is a top view of a diaphragm carriage in accordance withone aspect of the present invention;

[0058]FIG. 41 is a diagrammatic side view of the diaphragm carriage ofFIG. 40;

[0059]FIG. 42 is a top view of the diaphragm carriage of FIG. 40,similar to FIG. 40, but with a nailing carriage and a lifting carriagebeing raised;

[0060]FIG. 43 is a diagrammatic side view, similar to FIG. 41, with thenailing carriage and the lifting carriage being raised as is FIG. 42;

[0061]FIG. 44 is a diagrammatic side view showing a beginning stage oflifting of a diaphragm by the lifting carriage of the diaphragmcarriage;

[0062]FIG. 45 is a diagrammatic side view, similar to FIG. 44, showingthe diaphragm removed from the diaphragm stack;

[0063]FIG. 46 is a diagrammatic side view, similar to FIG. 45, with thediaphragm carriage beginning movement toward the assembly station;

[0064] FIGS. 47-50 are diagrammatic views showing a sensor arrangementthat may be used to determine the location and orientation of adiaphragm held by the diaphragm feeder, and a diaphragm being orientedrelative to the sensors to determine its location and orientation;

[0065]FIG. 51 is a diagrammatic side view showing a diaphragm held bythe lifting carriage over the assembly station;

[0066]FIG. 52 is a diagrammatic side view, similar to FIG. 51, with thediaphragm lowered against subpurlins and a purlin;

[0067] FIGS. 53-58 are diagrammatic side views showing a nailing processfor a nailing carriage of the diaphragm carriage in accordance with oneaspect of the present invention;

[0068]FIG. 59 is an end view of the nailing carriage of FIGS. 53-58;

[0069]FIG. 60 is a diagrammatic view of automatic nailers for thenailing carriage of FIG. 59, shown relative to a portion of the liftingcarriage;

[0070]FIG. 61 is a diagrammatic view of nailing stations for theautomatic nailers of FIG. 60;

[0071]FIG. 62 is a flow diagram generally representing exemplary stepsfor automatically producing a roof panel structure in accordance with anaspect of the present invention;

[0072]FIG. 63 is a flow diagram generally representing steps forinserting a purlin into the assembly station in accordance with anaspect of the present invention;

[0073]FIG. 64 is a flow diagram generally representing steps forindexing a purlin through the assembly station as subpurlins anddiaphragms are added to the purlin in accordance with an aspect of thepresent invention;

[0074]FIG. 65 is a flow diagram generally representing steps for loadinga subpurlin into the subpurlin clamping mechanisms in accordance with anaspect of the present invention;

[0075]FIG. 66 is a flow diagram generally representing steps foradvancing a subpurlin via the subpurlin clamping mechanisms into theassembly station in accordance with an aspect of the present invention;

[0076]FIG. 67 is a flow diagram generally representing steps foradvancing a diaphragm into the assembly station in accordance with anaspect of the present invention;

[0077] FIGS. 68-73 are diagrammatic representations of a nailingsequence that may be performed by roof panel structure assemblymechanism in accordance with one aspect of the present invention.

DETAILED DESCRIPTION

[0078] In the following description, various aspects of the presentinvention will be described. For purposes of explanation, specificconfigurations and details are set forth in order to provide a thoroughunderstanding of the present invention. However, it will be apparent toone skilled in the art that the present invention may be practicedwithout the specific details. Furthermore, well-known features may beomitted or simplified in order to not obscure the present invention.

[0079] Roof Panel Structures

[0080] Generally described, the present invention is directed to amechanism, generally designated as 100 in FIG. 1, for assembling roofpanel structures, an example of which is generally designated as “A” inFIG. 2. Although the roof panel structure A is shown as one example,variations of that structure are possible, and a person of skill in theart may utilize the features of the present invention in theconstruction of roof panel structures having various configurations.

[0081] As is known in the art, a roof panel structure A typicallyincludes a major horizontal beam, often called a purlin P. The purlin Pmay be a steel girder, a glulam structure, a wooden beam, or the like,but typically includes wood or another material along a top edge thatpermits easy attachment of other components of the roof panel structure(e.g., by nailing).

[0082] Minor beams, called “subpurlins” (S in FIG. 2) extendorthogonally to the purlin P, and are often attached to the purlin P byright angle brackets B that extend from an end of the subpurlin. Thesubpurlins S may be made of any of the materials described with abovewith respect to purlins P, but are typically lumber stiffeners, such as2-by-6's or 2-by-4's, 3-by-4's, 3-by-6's, and so forth, six to ten feetin length.

[0083] Diaphragms D, such as wood structural panels (e.g., 4×8, 4×10,8×8, or 8×10 structural wood panels) are mounted over the subpurlins Sand the purlin P, and are typically nailed to the subpurlins and thepurlin for structural and shear support. In the embodiment shown in FIG.2, the diaphragms D extend beyond both ends of the subpurlins S, and afront end of the diaphragms overlaps approximately one half of thethickness of the purlin P. The back ends of the diaphragms on anadjacent roof panel structure A overlap the other half of the thicknessof the purlin P. Subpurlins S are located such that the edges of thediaphragm D overlap one half of the subpurlins that extend along theside edges of the diaphragm, and other, intermediate subpurlins (twoshown in FIG. 2, but this number may be varied) are spaced between thetwo subpurlins on the side edges. Adjacent diaphragms D overlap theother half of the subpurlins S at the side edges.

[0084] The number of diaphragms D and subpurlins S used in a roof panelstructure A depends upon the spacing of the subpurlins, the width of thediaphragms, and the length of the roof panel structure. Typically, thediaphragms are 4 or 8 feet in width (although they may be less or morewide), and the subpurlins are typically spaced 24 inches on center(i.e., two edge subpurlins S and one intermediate for a 4 foot widediaphragm, and two edge subpurlins and three intermediate subpurlins fora 8 foot wide diaphragm, and so forth). Completed roof panel structuresA may be 25 to 80 feet in length, or even longer. When installed, theseroof panel structures A extend orthogonally to main supporting beams(not shown, but known in the art) and are attached to the mainsupporting beams and adjacent roof panel structures by nailing oranother appropriate attachment method.

[0085] General Overview

[0086]FIG. 1 shows a perspective view of a roof panel structure assemblymechanism 100 in accordance with the present invention. Parts have beenremoved for detail. In summary, the roof panel structure assemblymechanism 100 includes a purlin feeder 102, subpurlin feeders 104,subpurlin clamping mechanisms 106, and a diaphragm feeder 108. Thestructure and operation of an embodiment for each of these differentcomponents is described further below. However, in general, the purlinfeeder 102 advances a purlin P into an assembly station, generally shownat 110 in FIG. 1. The subpurlin feeders 104 insert a subpurlin S intoeach of the subpurlin clamping mechanisms 106, and the subpurlinclamping mechanisms advance into the assembly station 110 and hold thesubpurlins against the section of the purlin P that is already in theassembly station. The diaphragm feeder 108 places a diaphragm D onto thesubpurlins S and the purlin P at the assembly station 110.

[0087] The components shown in FIG. 1 are arranged relative to oneanother in one possible configuration. However, as will be understoodfrom the following description, the components may be arrangeddifferently. As nonlimiting examples, one or more of the purlin feeder102, the diaphragm feeder 108, the subpurlin feeders 104, and thesubpurlin clamping mechanisms 106 may be located above another of thesecomponents, or two components may be located on the same side of theassembly station (e.g., side by side), or one or more of the componentsor parts of the components may be located above or below the assemblystation. In addition, the functions of two or more of the purlin feeder102, the diaphragm feeder 108, or the subpurlin clamping mechanisms 106may be combined in a single station, or one or more of their functionsmay be provided at the assembly station 110. In addition, the featuresand operation of any of the components may be distributed over multiplecomponents or devices. As an example, one or more subpurlins and one ormore diaphragms may be advanced to a first assembly station where theyare attached, e.g., by nailing. The assembled structure may then beadvanced to a second station where it is attached to a purlin (which maybe advanced into the second station as well). As another alternative,the purlin may be advanced into the first assembly station, where it maybe attached to the assembled diaphragm and subpurlin structure. Multiplevariations are available.

[0088] Thus, multiple different arrangements are available for thepurlin feeder 102, the diaphragm feeder 108, the subpurlin clampingmechanisms 106, and the assembly station 110. In addition, the functionsof these components may be combined, or may be distributed over multiplestations. For ease of understanding, however, the invention will bedescribed with reference to the arrangement shown. However, a person ofskill in the art could modify the arrangement according to spaceconstraints or particular needs.

[0089] In accordance with one aspect of the present invention, after thepurlin P, the subpurlins S, and the diaphragm D are brought together inthe assembly station 110, the components are attached, for example byone or more automatic nailers (e.g., nailing guns). The purlin P is thenadvanced so that additional subpurlins S and a diaphragm D may beattached. This process proceeds until the end of the purlin P isreached.

[0090] The automatic nailers in the described embodiment are provided ona nailing carriage that moves with the diaphragm feeder. However, theautomatic nailers may alternatively be provided on a separate carriage,and may be positioned where convenient. In addition, although thedescribed embodiment discloses a nailing operation that occurs after thepurlin P, subpurlins S, and diaphragm D have been assembled, a nailingoperation may be used where subassemblies are assembled and attached(e.g., subpurlins and one or more diaphragms), and the subassemblies arethen advanced to be joined with the remaining portions of the roof panelstructure A (e.g., the purlin). Thus, automatic nailers may bedistributed over multiple locations. Moreover, as used herein,“carriage” is meant to denote a movable part of the roof panel structureassembly mechanism 100 that may be used to deliver the respective objector part, such as the automatic nailers for the nailing carriage.

[0091] The forward end of the purlin P that has subpurlins S anddiaphragm(s) D attached thereto advances into an exit station 112. Theexit station 112 includes supports for the assembled roof panelstructure A, as described further below. The purlin P continues to indexinto the exit station 112 until the assembled roof panel structure Aexits the assembly station 110. The assembled roof panel structure A isthen ready for removal from the exit station, and installation in aroof.

[0092] The components shown in FIG. 1 may be made portable, and thus maybe transported to a work site for assembly of roof panel structures A onthe site. As an example, a frame 120 for housing the subpurlin feeders104 and the subpurlin clamping mechanisms 106 may be formed integralwith a frame 122 for the diaphragm feeder 108. This integral unit may besized so that it may be transported on a single trailer. In addition, aframe 124 for the purlin feeder 102 and a frame 126 for the exit station112 may be integrally formed and sized so that the integral unit fits ona trailer. However, for the embodiment shown in the drawings, these twoframes 124, 126 are separate, but individually may be transportedtogether on a trailer or may be transported on separate trailers. Theframes 124, 126 may include attachment structures so that they may befixed to the frames 120, 122 once the roof panel structure assemblymechanism 100 has been placed at a site. The attachment of the frames120, 122, 124, 126 assures that proper alignment of the various stationsis maintained.

[0093] Although not shown so that details of the components of the roofpanel structure assembly mechanism 100 are visible, the subpurlin frame120 and the diaphragm frame 122 may include paneling on their outersurfaces. The paneling provides safety and security for the roof panelstructure assembly mechanism 100. Other paneling or appropriate coveringmay be incorporated in the roof panel structure assembly mechanism 100.

[0094] The frames 120, 122, 124, and 126 and the other components of theroof panel structure assembly mechanism 100 may be made steel. Othermaterials may be used, such as aluminum or other metals, wood for somecomponents, and/or plastics or composites. However, the applicant hasfound that steel is a relatively inexpensive material that providesstrength, wear resistance, and manufacturability.

[0095] The operation of the roof panel structure assembly mechanism 100may be controlled by a computer 128 (shown generally by a large box inFIG. 1, but its size and location may be altered as appropriate). Thecomputer 128 may be any device or devices that can executecomputer-executable instructions, such as program modules. Generally,program modules include routines, programs, objects, components, datastructures and the like that perform particular tasks or implementparticular abstract data types. Given the description herein, thecomputer 128 may be programmed by a programmer of ordinary skill toperform the functions and operations described herein. Although theinvention is described with reference to a single computer 128, thefeatures of the computer 128 may be distributed over a number ofcomputers, microcomputers, controls, or other devices.

[0096] Unless described otherwise herein, the operation of the roofpanel structure assembly mechanism 100 is fully automated, and thefunctions of the roof panel structure assembly mechanism are drivensynchronously by the computer 128 with relatively little operatorintervention. However, if desired, one or more of the functions of theroof panel structure assembly mechanism 100 may be performed manuallyinstead of automatically, but without the full benefits of the describedembodiment.

[0097] The Purlin Feeder

[0098] The station for the purlin feeder 102 is shown in detail in FIG.3. One or more hoists 130 may be provided for lifting a purlin P (shownfor simplification in phantom in FIG. 3, but the structure of which isknown in the art) onto a series of lifting mechanisms 132. The hoist 130or hoists may be, for example, a single boom hoist, having a hook 134and being capable of rotation, as shown by the arrows 136. As shownphantom in FIG. 3, more than one hoist may be incorporated into thepurlin feeder station 102. Purlins P may be stacked on the frame 124,and thus are easily accessible by the hoist 130 or by an operator. Thehoist 130 is used to aid a worker in placing a purlin on the liftingmechanisms 132, but is not necessary for operation of the presentinvention.

[0099] The details of one of the lifting mechanisms 132 are shown inFIG. 4. The lifting mechanism 132 is mounted on the frame 124, andincludes a vertical column 140. The vertical column 140 has a crosssection of a “U,” with sides of the U being formed by connected,parallel I-beams.

[0100] A carriage 142 is mounted for sliding movement up and down theface of the vertical column 140. The carriage 142 includes wheels 144(only one of which is shown in FIG. 4) that allow the carriage tosmoothly glide up and down the vertical column 140. A bolt 146 or otherfastener extends out of the back of a front plate 148 for the carriage142, and is connected to an endless belt or chain 150. The chain 150loops around an idler sprocket 152 at the top of the vertical column140, and a drive sprocket 154 at the bottom of the vertical column 140.The drive sprocket 154 is arranged to engage teeth (not shown) on ahorizontal shaft 156.

[0101] In accordance with one aspect of the present invention, thestructure thus described for the lifting mechanism 132 is included oneach of the lifting mechanisms. In addition, the shaft 156 is common toall the lifting mechanisms for the purlin feeder 102, i.e., connects tothe drive sprocket 154 for each of the lifting mechanisms.

[0102] A plate 160 extends horizontally outward from the bottom of thecarriage 142. In accordance with one aspect of the present invention,for some of the lifting mechanisms (e.g., the right three in FIG. 3),the plate includes a roller 162 or rollers along a top edge. For others(e.g., the left three in FIG. 3), the plate 160 includes a pair of siderollers 164 (best shown in FIG. 4). The side rollers 164 are arranged toengage and receive side edges 166 of a roller bar 168. The roller bar168 includes a series of rollers 170 along its top surface.

[0103] The side rollers 164 permit the roller bar 168 to extend beyondthe frame 124 of the purlin feeder 102 and into the assembly station110. That is, the roller bar 168 may extend from the position shown inFIG. 3, where it is captured by the side rollers 164 on three liftingmechanisms 132, to the extended position shown in phantom in FIG. 5. Inthis extended position, the roller bar 168 is supported by the leftmosttwo lifting mechanisms 132, and the forward portion of the roller bar168 extends well into the assembly station 110. A stop may be providedto prevent the roller bar 168 from extending too far forward. Byextending into the assembly station 110, the roller bar 168 continues toprovide support for a purlin P after the purlin has left the purlinfeeder 102.

[0104] In operation, a purlin P is lifted by the hoist 130 (ifavailable), and is swung over to the lifting mechanisms 132. A purlin Pis shown at the beginning stage of lifting in FIG. 5. If not alreadyextended into the assembly station 110, the roller bar 168 may be thusextended prior to lifting the purlin P. Alternatively, the roller bar168 may be extended with a purlin P.

[0105] The purlin P, once installed on the lifting mechanisms 132 (FIG.6), rests on the rollers 162 and the rollers 170 (e.g., the purlin P isshown on the rollers 170 in FIG. 6). To this end, the rollers 162 andthe rollers 170 are arranged so that their top edges are aligned. Thepurlin P may lean against the vertical columns 140 for stability. Ifdesired, other rollers (not shown) may be provided on the verticalcolumn 140 to aid in advancing a purlin P.

[0106] After the purlin P is placed on the lifting mechanisms 132, thelifting mechanisms 132 may then raise or lower the purlin P so as toalign the top of the purlin with a reference point. This feature isimportant for the embodiment of the invention shown in the drawings,because the purlin P should be at a particular level for the subpurlinsto properly align with the top of the purlin in the assembly station. Inalternate embodiments, the height of the subpurlins S may be altered toalign with the purlin P, for example, or the subpurlins and purlin maybe aligned in other manners.

[0107] To adjust the height of the purlin P, the shaft 156 is rotated,as shown by the arrows 172 in FIG. 7. Rotation of the shaft 156 causesthe drive sprockets 154 to rotate, forcing the front loop of the chains150 upward. This movement drives the carriage 142 upward, lifting thepurlin along with it.

[0108] Because each of the lifting mechanisms 132 is driven by the sameshaft 156, the plates 160 move upward at the same rate. This featurepermits the purlin P to remain horizontal and fully supported duringlifting. The shaft 156 may be driven by a servo motor, shown generallyas a box 174 in FIG. 1.

[0109] The proper height may be determined by a user (e.g., by visualinspection against a reference), or may be sensed. If a sensor orsensors are used, then the sensors may shut power to the servo motor 174once the purlin P has reached the appropriate height.

[0110] After the purlin P is raised or lowered to the proper height, thepurlin P is ready for advancing into the assembly station 110. As such,the purlin P may be advanced (e.g., manually) on the rollers 162 and 170into the assembly station, as is shown in FIG. 5. As stated above,additional rollers (not shown) may be provided on the vertical columns140 to aid in smooth movement of the purlin P into the assembly station110. The roller bar 168, because it extends into the assembly station110, continues to support the purlin P as it is advanced. When thepurlin P reaches the assembly station 110, it is captured between atoothed driven roller 180 (FIG. 5) and a biased idler roller 182. Theidler roller 182 is pressed toward the toothed driven roller 180, asshown by the arrow 183, for example by a cylinder or spring (not shown).

[0111] Further within the assembly station 110, just forward of thetoothed driven roller 180, is a belt 184. The belt 184 is wrapped over anumber of rollers 186, one of which is shown in FIG. 5. The rotation ofthe outer surface of the belt 184 is synchronized with the rotation ofouter surface of the toothed driven roller 180. For example, the tootheddriven roller 180 and the rollers 186 and belt 184 may have the sameradius, and therefore would rotate at the same speed.

[0112] Once the purlin P is captured between the toothed driven roller180 and the idler roller 182, rotation of the toothed driven rollerpulls the purlin into the assembly station 110. The toothed surface ofthe toothed driven roller 180 helps to grip the purlin P, and the biasof the idler roller 182 assures constant engagement of the purlin P withthe toothed driven roller.

[0113] Either of the toothed driven roller 180 and the idler roller 182may include a sensor and/or a counter (not shown) for determining thestart of a purlin P, and for measuring the amount the purlin has beenadvanced into the assembly station 110. This feature may be provided,for example, by the toothed driven roller 180 being driven by anabsolute feedback servo motor (not shown). As is known, such motorsprovide feedback of their functions, even if power has been cut duringoperation. This feature helps to automatically feed the purlin P thecorrect amount into the assembly station, and to maintain informationregarding information about the position of the purlin as it advancesinto and through the assembly station 110. In addition, the amount thatthe idler roller 182 is biased inward may be sensed to determine orconfirm the thickness of the top of the purlin P.

[0114] As the purlin P continues to advance into the assembly station,it engages the belt 184, which helps maintain alignment of the purlin,and further helps to pull the purlin forward. The idler roller 182maintains the contact of the purlin with the front of the verticalcolumns 140 of the lifting mechanisms, the toothed driver roller 180,and the belt 184. In this manner, the purlin maintains proper alignmentas it enters and passes through the assembly station 110.

[0115] The lifting mechanisms 132 shown in the drawings are but one wayto provide lifting and feeding of the purlin P. For example, a singlecolumn may be used, having a roller bar stabilized thereon. A platformmay be provided, the height of which may be adjusted, and along whichthe purlin P may be fed. The purlin P may be captured between opposingrollers (up and down or side-to-side), or suspended from overhead. Manyalternatives are available. However, the described embodiment isrelatively inexpensive to fabricate, and provides exemplary stabilityand lifting ease.

[0116] The Exit Station

[0117] The exit station 112 is shown in detail in FIGS. 8 and 9. As theassembled panel A leaves the assembly station 110, it enters the exitstation 112. The exit station 112 includes a number of liftingmechanisms 190 that are similar to the lifting mechanisms 132 in thepurlin feeder 102. The lifting mechanisms 190 include passive rollers192 at their top edges, with an axis of rotation for each of the rollersbeing aligned vertically.

[0118] The lifters for the lifting mechanism 190 are similar inconstruction to the plates 160 and carriages 142 for the liftingmechanisms 132. In the embodiment shown in the drawings, the left-mostfive lifting mechanisms 190 include rollers similar to the right-mostthree lifting mechanisms 132. However, the two right-most liftingmechanisms 190 of the exit station 112 include a conveyor 196 extendingbetween the two plates 160 for the lifting mechanisms 190. When theassembled roof panel structures A leave the assembly station 110, thebottom edge of the purlin P aligns with and then rides along the top ofthe conveyor 196. The conveyor 196 may be driven by an absolute feedbackservo motor (not shown), and preferably is synchronized with the belt184 and the toothed driven roller 180.

[0119] The shaft or other mechanism that is used to raise the liftingmechanisms 190 may be similar to, or the same as, the shaft 156 used toraise the lifting mechanisms 132 for the purlin feeder 102. If separatemechanisms (e.g., separate shafts) are used to lift the two liftingmechanisms 132, 190, then the lifting of these two lifting mechanisms ispreferably synchronized so that the heights of the two mechanisms may bethe same, so that the purlin P may smoothly transition from the purlinfeeder 102, through the assembly station 110, and into the exit station112. As the purlin P enters and continues through the exit station 112,the top end of the purlin aligns against the rollers 192 on the top ofthe lifting mechanism 190.

[0120] A support 200 is provided on the opposite side of the exitstation 112 from the lifting mechanisms 190. The support 200 is arrangedand configured to receive a bottom edge of the subpurlins S as theassembled roof panel structure A advances through the exit station 112.

[0121] The support 200 includes an endless chain 202 running along itslength. The subpurlins rest against this endless chain 202. The rotationof the endless chain 202 is preferably synchronized with the movement ofthe conveyor 196, for example by an absolute feedback servo motor (notshown). Thus, the subpurlin end of the roof panel structure A is driventhrough the exit station 112 at the same rate that the purlin P isdriven through the exit station. The outer end of the support 200 iscanted slightly inward toward the lifting mechanisms 190 relative to theinner end, so that the subpurlin end of the assembled roof panelstructures A crowd or lead toward the lifting mechanisms 190. Thisfeature maintains the assembled roof panel structure A against therollers 192, and helps to maintain the alignment of the assembled roofpanel structure through the exit station 112.

[0122] The Forklift Tines

[0123] In accordance with one aspect of the present invention, a novelset of forklift tines 210 (FIG. 10) is provided for removing theassembled roof panel structure A from the exit station 112. The forklifttines 210 include an elongate bar 212 extending orthogonally to theforklift F. A series of T-bars 214 extend orthogonally from the elongatebar 212. The T-bars 214 are attached at their base to the elongate bar212 such that the top of the T-bars 214 is spaced from the elongate bar.The T-bars 214 are spaced from each other the same as the liftingmechanisms 190, and the length of the top of the T-bars 214 is less thanthe spacing between the lifting mechanisms 190.

[0124] The forklift tines 210 are rotatably mounted to the forklift, forexample, about an axle 216. This rotational mounting permits the tines210 to be rotated upward relative to the arms of the forklift F.Vertical bars 218 extend upward from the axles 216.

[0125] The use of the forklift tines 210 is shown in FIGS. 10-13. Afteran assembled roof panel structure A is complete, a forklift F having theforklift tines 210 mounted thereon is driven toward the exit station112, and the T-bars 214 are aligned between the lifting mechanisms 190and under the assembled roof panel structure A. The T-bars 214 areinserted until the elongate bar 212 is adjacent the lifting mechanisms190. The tines 210 are then rotated about the axle 216, and the arms ofthe forklift F are raised such as to remove the assembled roof panelstructure from the exit station 112. The assembled roof panel structureA may then be rotated about the axle 216 and lifted by the arms of theforklift F as appropriate so as to place the roof panel structure inposition for installation. The roof panel structure A may at this pointbe resting against the vertical bars 218.

[0126] The Subpurlin Feeders

[0127]FIG. 14 shows the subpurlin frame 120 and the diaphragm frame 122,with the purlin frame 124 and the exit station 112 removed for detail.FIG. 15 shows a detail view of a rear portion of the subpurlin clampingmechanisms 106 and the subpurlin feeders 104. In summary, as describedabove, the subpurlin feeders 104 are configured and arranged to depositsubpurlins S into the subpurlin clamping mechanisms 106. The subpurlinclamping mechanisms 106 then advance into the assembly station 110, withthe subpurlins S therein, so that the subpurlins may be aligned with andattached to the purlin P and the diaphragms D. To this end, thesubpurlin clamping mechanisms 106 are mounted on a subpurlin carriage220, shown in FIG. 15. The operation and structure of the subpurlincarriage 220 and the subpurlin clamping mechanisms 106 are furtherdescribed below.

[0128] The subpurlin feeder 104 may be any structure that is arrangedand configured to deposit subpurlins S into the subpurlin clampingmechanisms 106. In one example shown in the drawings, each subpurlinfeeder 104 is a magazine that is designed to hold a plurality ofsubpurlins S, and to drop one subpurlin into an empty subpurlin clampingmechanism 106.

[0129] A rear view of the subpurlin feeders 104 is shown in FIG. 16.Each of the subpurlin feeders 104 includes a vertical wall 224 that isfixed in position. An adjustable vertical wall or bracket 226 extendsparallel to the fixed vertical wall 224. Each of these walls 224, 226may extend along the length of the subpurlin frame 120 or any portionthereof, but the walls are preferably arranged to maintain subpurlins Stherebetween, arranged in the direction of the assembly station 110.

[0130] The adjustable vertical wall 226 is rotatably attached to a fixedframe 228 by a pair of lever arms 230, 232. As can be seen in FIG. 17,one of the lever arms 232 includes a cylinder 234 eccentrically mountedthereon. The opposite end of the cylinder 234 is attached to the frame228. Extending the cylinder 234 causes the two lever arms 232, 230 torotate, pushing the adjustable wall 226 outward relative to the frame228 and toward the fixed vertical wall 224.

[0131] The adjustable vertical wall 226 and its movement permit thespacing between the adjustable vertical wall 226 and the fixed verticalwall 224 to be adjusted to various different thicknesses of subpurlinsS. As such, the two walls 226, 224 may be appropriately spaced so thatsubpurlins can be stacked edge to edge within and between the two walls,without permitting the subpurlins S to rotate or bind between the twowalls.

[0132] The subpurlin feeders 104 may be sized to hold an appropriateamount of subpurlins S, given space constraints and the desire of themanufacturer. The subpurlins S may be manually fed into the subpurlinfeeders 104, or some type of automated input of the subpurlins S may beprovided. The subpurlin feeder 104 may include sensors (not shown) fordetermining that the subpurlins need to be replenished in the subpurlinfeeder. These sensors may be provided, for example, by eye sensors,contact sensors, or weight sensors.

[0133] The spacing between the walls 224, 226 may be set according tothe subpurlins S that are located in the subpurlin feeders 104. Thespacing between the two walls 226, 224 may be set, for example, by thecomputer 128 in response to operator input, may be manually set by anoperator, or may be automatically set based upon a sensing of the widthof the subpurlins S. In general, however, the spacing is slightly morethan the width of the subpurlins S, e.g., two inches for 2×6's, and soforth.

[0134] A plunger 240 is mounted on the frame 228 so that it aligns withthe second from the bottom, or penultimate subpurlin S. In theembodiment shown in the drawings, there are two of these plungers 240per subpurlin feeder 104 (FIG. 19).

[0135] In addition, a swivel-mounted support arm 242 is attached forrotation adjacent to the bottom of the fixed vertical wall 224. As canbe seen in FIG. 18, the support arm 242 is fixed to rotate with a rod244 that extends through a bracket 246 on the fixed vertical wall 224. Apivot arm 248 is attached for rotation with the rod 244 and extendsoutwardly from the top of the rod. The pivot arm 248 is attached to alever arm 250. The lever arm 250 attaches to a similar pivot arm 248 onanother end of the purlin feeder 104, as can be seen in FIG. 19.

[0136] A plunger 252 (FIG. 19) is attached to an end of the lever arm250. Operation of the plunger 252 causes the lever arm 250 to retractwhich, in turn, causes the pivot arm 248 to rotate, rotating the supportarm 242. Rotation of the arms is shown in FIG. 20. As the support arms242 rotate, they move out of the way of the bottom subpurlin S,permitting the bottom subpurlin to fall into the subpurlin clampingmechanism 106. A subpurlin S that has dropped into the clampingmechanism 106 is shown in FIGS. 21 and 22. The subpurlins S mayalternatively be dropped or placed in the subpurlin clamping mechanisms106 in different ways.

[0137] Before the lever arm 250 is used to rotate the support arms 242,the plungers 240 are extended to hold the penultimate subpurlin S inplace. The plungers 240 continue to hold the penultimate subpurlin Sduring rotation of the support arms 242. In this manner, the penultimatesubpurlin S and all subpurlins above the penultimate subpurlin aresupported as the bottom subpurlin drops. After the lower subpurlin S hasbeen dropped, the plunger 252 extends, causing the support arms 242 toalign back under the stack of subpurlins S. The plungers 240 thenretract, allowing the penultimate subpurlin and the subpurlins S abovethe penultimate subpurlins to drop into place. The purlin feeder 104 isthen ready for dropping of the next subpurlin S.

[0138] The Subpurlin Clamping Mechanisms

[0139] As stated above, the subpurlin clamping mechanisms 106 aremounted on a subpurlin carriage 220. The carriage 220 includes acarriage frame 256 having wheels 258 (FIG. 23). In operation, subpurlinsS are provided to the subpurlin clamping mechanisms 106 by the subpurlinfeeders 104, and the subpurlin carriage 220 moves the subpurlin clampingmechanisms from the subpurlin feeders to the assembly station 110.During this movement, the subpurlin carriage wheels 258 roll along rails259. The movements of the subpurlin carriage 220 and its components maybe operated by absolute feedback motors, such as absolute feedback servomotors. As such, the location of the components of the subpurlincarriage and the speeds of the operation may be easily altered by thecomputer 128 or by a programmer or operator via the computer 128, ormay, for example, be moved precisely to a location based upon input fromsensors or the computer.

[0140] Details of the subpurlin clamping mechanisms 106 can be seen inFIGS. 23 and 24. The subpurlin clamping mechanisms 106 include slots 260for receiving the subpurlins S. The slots 260 include left rails 262 andright rails 264. These rails 262, 264 are mounted on a clampingmechanism frame 266. The clamping mechanism frame 266 is pivotallymounted to the carriage frame 256, for example via a pivot rod 268. Thepivot rod 268 is shown in FIGS. 22 and 23, and the function of theclamping mechanism frame 266 pivoting relative to the carriage frame 256is described below.

[0141] Mounted along the length of the subpurlin clamping mechanisms 106are a number of clamping, or pinching mechanisms 270. In the embodimentshown, the number of pinching mechanisms 270 per subpurlin clampingmechanism 106 is three, but this number may be varied. The pinchingmechanisms 270 are configured to center the subpurlins S in thesubpurlin clamping mechanisms 106, and to hold the subpurlins inposition once centered. In addition, as further described below, thepinching mechanisms 270 include sensors that detect the thickness of thesubpurlins in the subpurlins clamping mechanisms 106.

[0142] Details of one of the pinching mechanisms 270 are shown in FIGS.25 and 26. The pinching mechanisms 270 include two different sides thatare mirror images of one another. For simplicity, only one side isdescribed.

[0143] The pinching mechanisms 270 include a bracket 272 mounted on theoutside of the slots 260. A rod 274 is rotatably mounted in the bracket272. A toothed gear 276 is mounted for rotation with the rod 274 at abottom end of the rod. An eccentrically mounted arm 278 is mounted onthe top end of the rod, also for rotation with the rod 274. Ahalf-circular contact 280 is mounted on the end of the eccentricallymounted arm 278.

[0144] A counter-type sensor 282 is mounted on the outside of thetoothed gear 276, and is arranged and configured to index a unit as eachtooth of the gear 276 passes through the sensor. The sensor 282 islocated on only one side of the pinching mechanism 270. A bar 284 havingteeth along its outer edges engages the toothed gear 276 on each side ofthe pinching mechanism 270.

[0145] In operation, the bar 284 is extended (e.g., by a cylinder, notshown) after a subpurlin S has dropped into the slot 260. This extensioncauses the toothed gears 276 to rotate, forcing the half-circularcontacts 280 inward. The contacts 280 engage and maintain the subpurlinS in the center of the slot 260. In addition, the counter/sensor 282provides real-time information to the computer 128 regarding the amountthat the gears 276 on at least one side of the pinching mechanism 270have rotated, and therefore the width of the subpurlin S may beconfirmed or detected.

[0146] The subpurlin clamping mechanisms 106 each include a cylinder 286at the trailing end. The cylinders 286 include a rod 288 having a T-bar290 mounted at a distal end. The outer edges of the T-bar 290 engageleft and right tracks 292, 294. A sensor/counter 296 is mounted alongone side of the rod 288.

[0147] During operation, after a subpurlin S has been inserted into theslot 260, and the pinching mechanisms 270 have closed around thesubpurlin, the carriage 220 moves into the assembly station 110. At theend of this movement, the cylinders 286 drive the subpurlin S againstthe purlin P, as further described below. The T-bar 290 engages thetracks 292, 294, preventing the rod 288 from rotating, thus providing anaccurate reading for the sensor 296, and preventing the subpurlins frombeing twisted out of the subpurlin clamping mechanisms 106.

[0148] At the front end of the subpurlin carriage 220 is mounted a pairof push bars 300. Each of the push bars 300 includes a roller 302mounted at its top, with a vertical axis of rotation. A bolt 304 extendsthrough the bottom of the push bar and attaches the push bar to theclamping mechanism frame 266 or the carriage frame 256. A spring 306 ismounted on the bolt and biases the bolt and the push bar 300 into anupright position. A stop 308 and a pair of second bolts 310 operate tomaintain the position of the push bar 300 in the upright position, alongwith the spring 306 and the bolt 304.

[0149] During operation, as the subpurlin carriage 220 is extendedforward, the roller 302 engages the purlin P, and the push bar 300rotates backward around the second bolts 310 and against the bias of thespring 306. As such, the push bar 300 helps to assure that the purlin Pis pressed appropriately against the belt 184. Because the width of thepurlin P is known, the subpurlin carriage 220 may be stopped at theappropriate location by the use of the absolute feedback servo motorthat drives the subpurlin carriage. As an example, the subpurlincarriage 220 may stop at a location where the push bar 300 is bentbackward approximately ¼ inch.

[0150] The subpurlin carriage 220 includes an assembly support 312,shown in FIGS. 27, 28 and 29. The assembly support 312 includes rollers314 along its top edge, and is mounted on a pair of extension bars 316.The extension bars 316 are mounted between two pinch rollers 318 so thatthe extension bars 316 may extend outward and forward relative to thesubpurlin carriage 220. The extension bars 316 include teeth along alower surface for engaging a gear 320, shown schematically in FIG. 30.

[0151] As shown in FIG. 30, the gear 320 is attached, via a clutch 322,to the drive train 324 for the subpurlin carriage 220. The drive train324 is connected to a motor 321, which drives gears 328 for extendingthe subpurlin carriage 220. The gears 328 may, for example, engage agear rack (not shown) on the frame 120. The drive train 324 is linked toan intermediate axle 323 via a drive chain 325. The clutch 322 isarranged between the drive chain 325 and a second chain 326, which isconnected to the axle 327 for the gears 320.

[0152] The gear ratio for the gear 320 is preferably the same as theratio for the drive for the subpurlin carriage 220. However, the gear320 is arranged to drive the assembly support 312 in the oppositedirection of the subpurlin carriage 220, and the clutch 322 is operativeto engage upon retraction of the subpurlin carriage 220. Thus, when theclutch 322 is engaged, the assembly support 312 moves outward relativeto the subpurlin carriage 220 at a rate that is substantially equal tothe rate in which the subpurlin carriage is moving rearwardly. Thus,during this movement, the assembly support 312 appears to be stationaryas the subpurlin carriage 220 is moving rearward. When the assemblysupport 312 moves outward, it is positioned to support the subpurlin anddiaphragm end of the assembled roof panel structure A, after thesubpurlins S and diaphragm D have been attached, so that the assembledroof panel structure A may move into the exit station 112 by rolling onthe rollers 314. The clutch 322 may also include a brake so that theassembly support may be stopped after extension.

[0153] The operation of the subpurlin clamping mechanisms 106, aftersubpurlins S have been installed in the subpurlins clamping mechanisms106, is shown in FIGS. 31-38. Beginning at FIG. 31, the subpurlinfeeders 104 drop subpurlins S into the subpurlin clamping mechanisms106. Then, at FIG. 32, the subpurlin carriage 220 moves forward with thesubpurlin clamping mechanisms 106, and toward the assembly station 110.

[0154] When the subpurlin carriage 220 enters the assembly station, apurlin P is already in place. If the brackets B are used for thesubpurlin S, there is a possibility that the edge of the bracket may hitthe subpurlin S. For this reason, in accordance with one aspect of thepresent invention, a lift is provided on the front edge of the clampingmechanism frame 266 for raising the front edge of the subpurlins Sbefore they reach the purlin P. In the embodiment shown in the drawings,the lift is provided as an air bag or air bags 330. The air bags 330 mayalternatively be air cylinders, mechanical lifts, or any other suitabledevice for lifting the front end of the subpurlins S. The air bags 330fire as the subpurlin S approaches the purlin P, thereby lifting thebracket B to clear the top edge of the purlin. The beginning of thismovement is shown in FIG. 33, and is shown in close detail in FIG. 34.In FIG. 33, the purlin P has been removed to show detail, but in FIG. 34it is shown, demonstrating how lifting the front end of the subpurlins Scauses the bracket B to clear over the top edge of the purlin P.

[0155] While the front end of the subpurlin S is lifted, the subpurlincarriage 220 continues to move toward the purlin P. In an exemplaryembodiment, the air bags 330 fire during the movement of the subpurlincarriage 220, and thus its movement does not slow until slowed byslowing of the motor 321 that drives the subpurlin carriage 220 (i.e.,when the subpurlin approaches the purlin). As the subpurlin S isadjacent the purlin P, the push bar 300 engages the purlin P, ensuringthat the purlin is pushed against the belt 184.

[0156] After the subpurlin S has abutted against the purlin P, thecylinder 286 presses the subpurlin against the purlin, while the sensors296 confirm or determine the length of the subpurlin. The air bags 330may then be released, allowing the bracket B to rest against the top ofthe purlin P, as shown in FIGS. 35 and 36.

[0157] After the subpurlin S is attached to the purlin P (describedfurther below), the subpurlin carriage 220 retracts, as shown in FIG.37. When it has retracted approximately halfway, the assembly support312 is released, by engaging the clutch 322. As the subpurlin carriage220 continues to retract, the assembly support 312 remains in the samelocation, so that it may support the end of the subpurlins S, as shownin FIG. 38. The subpurlins S are supported on the wheels 314, and mayroll toward the exit station 112 on these wheels as the purlin P isadvanced through the assembly station 110.

[0158] The Diaphragm Feeder

[0159] The diaphragm feeder 108 is designed to advance a diaphragm Dinto the assembly station 110. The diaphragms D, in the shownembodiment, are provided on a diaphragm lift 340 (FIG. 39). Thediaphragm lift 340 includes a stack of the diaphragms D on top of aplatform 341. The platform 341 is mounted on a scissors lift 342. Thescissors lift 342 may include appropriate cylinders or other liftingdevices such as is known in the lift art. Through the use of weight orposition sensors, the lift 340 may maintain a top diaphragm D in thestack at a consistent height, such that as diaphragms are removed, thescissors lift 342 indexes upward to maintain the top diaphragm at thisconsistent level. Wheels 344 may be provided on the bottom of thediaphragm lift 340 so that the lift may be moved in and out of thediaphragm feeder station for service or to replenish the stack ofdiaphragms D.

[0160] In accordance with one aspect of the present invention, thediaphragm feeder 108 includes a diaphragm carriage 346. In the shownembodiment, a lifting carriage 350 and a nailing carriage 352 areconfigured to travel with the diaphragm carriage 346. The liftingcarriage 350 is configured to lift a diaphragm D from the diaphragm lift340 and to properly position the diaphragm, and then place the diaphragmin the assembly station 110. The nailing carriage 352 is configured tomove automatic nailers 348 (FIG. 41) into place so that the nailers maynail the diaphragms D to the subpurlins S and the purlin P. Thestructure and operation of the nailing carriage 352 and the liftingcarriage 350 are further described below.

[0161] Turning now to FIG. 40, the lifting carriage 350 is suspendedfrom a horizontal beam 354 by a swivel attachment 356. The horizontalbeam 354 is suspended from a pair of cross beams 358 that extendorthogonally to the horizontal beam. These cross beams 358, in turn, aresuspended from a pair of orthogonally arranged cross beams 360.

[0162] The lifting carriage 350 includes a manifold 362 (FIG. 41) havinga central beam 364 (FIG. 40). A number of suction cups 366 are attachedto the manifold 362 and are fluid communication with the manifold. Themanifold 362 is also connected to a vacuum system (not shown).

[0163] Returning now to FIG. 40, a worm gear 368 extends from the crossbeam 364 on the manifold 362 to the cross beam 360. A second worm gear370 is included between the attachment of the horizontal beam 354 andthe cross beam 358. A third worm gear 372 is attached between the crossbeams 358 and the orthogonally arranged cross beam 360.

[0164] The three worm gears 368, 370, 372 provide rotational, x-, andy-movement of the lifting carriage 350 relative to the nailing carriage352. The movements of the worm gears 368, 370, 372 may be operated byabsolute feedback motors, such as absolute feedback servo motors. Assuch, the location of the lifting carriage 350 and the speeds of theoperation of the worm gears 368, 370, 372 may be easily altered by aprogrammer or operator via the computer 128, or may be performedautomatically by the computer. In addition, the automatic feedbackmotors permit the lifting carriage 350 to be accurately located relativeto the nailing carriage 352, and for that location to be known to thecomputer at all times.

[0165] Operation of the worm gear 368 causes the beam 364 of themanifold 362 to rotate, causing the lifting carriage 350 to rotate aboutthe swivel attachment 356 in the direction of the arrows 374. Operationof the worm gear 370 causes the horizontal beam 354 to move along thecross beams 358, moving the horizontal cross beam in the direction ofthe arrows 376. Operation of the worm gear 372 causes the cross beams358, and therefore the horizontal beam 354 and the lifting carriage 350,to move along the linear bearings 378, in the direction of the arrow379. All of these movements may be controlled by the computer 128, andare smooth because of the use of the worm gears 368, 370, and 372. Othermechanisms may be used for providing the rotational, x- andy-directional movements.

[0166] The Nailing Carriage

[0167] The nailing carriage 352 includes a number of automatic nailers348 suspended therefrom. The automatic nailers 348 may be, for example,nailing guns or other devices which are capable of pneumatically,mechanically, or otherwise driving fasteners for attaching thediaphragms D to the subpurlins S and the purlin P. As another example,the automatic nailers may be replaced with automatic screw drivers orother appropriate fastener drivers. Alternatively, if metal componentsare used for the roof panel structure A, the automatic nailers 348 maybe welders.

[0168] The nailing carriage 352 may be suspended from the cross beams360. The cross beams 360 are mounted on linear bearings 382 that providelateral movement in the direction up and down in FIG. 40 of both thenailing carriage 352 and the lifting carriage 350. A worm gear or otherappropriate mechanism may be provided for movement of the cross beams360 relative to the linear bearings 382.

[0169] The lifting carriage 350 and the nailing carriage 352 may also bemoved to the left and right in FIG. 40 by rotation of a gear 384 (FIG.41) that engages the rack 386. The gear 384 may be driven by anappropriate motor or other mechanism (not shown). To aid in movement ofthe lifting carriage 350 and the nailing carriage 352, the diaphragmcarriage 346 is suspended by wheels 388 (FIGS. 40 and 41), which runalong a track 389 (FIG. 40).

[0170] As described thus far, it is apparent that the lifting carriage350 may move in x, y, and rotational directions relative to the nailingcarriage 352. The nailing carriage 352 is fixed for movement with thecross beam 360. The lifting carriage 350, on the other hand, may moverelative to the cross beam 360 in the left to right direction in FIG.40, denoted by the arrow 349 and movement provided by the worm gear 372,in the up and down directions in that drawing, denoted by the arrow 376and provided by the worm gear 370, and in the rotational direction byswiveling about the swivel connection 356, denoted by the arrow 374 andprovided by the worm gear 368.

[0171] In addition to the above three degrees of movement, the nailingcarriage 352 and the lifting carriage 350 may be moved together in x andy directions. First, the two carriages 350, 352 may be moved up and downin FIG. 40 in the direction of the arrows 387 by moving the cross beams360 along the linear bearings 382. Second, the nailing carriage 352 andthe lifting carriage 350 may be moved left and right in FIG. 40 byrotation of the gear 384 and movement of the entire diaphragm carriage346 along the track 389.

[0172] A lift mechanism is provided to allow one more degree of movementfor the lifting carriage 350 and the nailing carriage 352. The liftmechanism permits the two carriages 350, 352 to move out of the page inFIG. 40, or upward. The lift mechanism may be provided in a number ofways, including, but not limited to, cylinders, air bags, and mechanicallifts, but a particular embodiment is shown in the drawing that utilizeswedges 390 that are driven under wheels 392. The lifting carriage 350and the nailing carriage 352 are suspended by the wheels 392. Drivingthe wedges 390 under the wheels 392 causes the lifting carriage 350 andthe nailing carriage 352 to be raised.

[0173] To permit the wedges 390 to be driven under the wheels 392, thewedges 390 are mounted for sliding movement on rails 394. The rails 394are mounted for movement along the outer edges of the diaphragmcarriage. Cross beams 396 extend between the two rails 394, such that arectangle is formed by the cross beams 396 and rails 394 (the rectangleis shown with stippling for ease of viewing). A rear drive 398, such asan absolute feedback servo motor, is attached to one of the cross beams396. The absolute feedback motor permits the location of the rectangleand the speed of the operation to be set by the computer 128, or to beeasily altered by a programmer or operator via the computer 128.Actuation of the rear drive 398 causes the wedges 390 to move relativeto the wheels 392, thus raising or lowering the lifting carriage 350 andthe nailing carriage 352. To assure that the movement of the liftingcarriage 350 and the nailing carriage 352 is vertical only, and notlateral, wheels 402 are connected to these carriages. The wheels 402 arearranged to move along plates 404 that are attached to the diaphragmcarriage 346. Engagement of the wheels 402 with the plates 404 preventslateral movement of the lifting carriage 350 and the nailing carriage352.

[0174] To aid in driving the wedges 390 under the wheels 392, a secondcylinder 400 may be provided that is attached to the front cross beam396. This cylinder 400 acts as a balancing cylinder for the rearcylinder 398, and permits a smaller sized cylinder to be used andsmoothes the lifting of lifting carriage 350 and the nailing carriage352 relative to the diaphragm carriage.

[0175] Operation of the Lifting Carriage

[0176] Operation of the diaphragm feeder 108 begins with the diaphragmlift 340 in a raised position, with a diaphragm just below the liftingcarriage 350, such as is shown in FIG. 39. At this position, the liftingcarriage 350 and the nailing carriage 352 are in the raised position,with the wheels 392 driven upward by the wedges 390, such as is shown inFIGS. 42 and 43.

[0177] With the lifting carriage 350 centered over the stack ofdiaphragms D, the wedges 390 are driven from under the wheels 392,causing the lifting carriage 350 and the nailing carriage 352 to lower.At the lowered position, the suction cups 366 are lowered downward intocontact with the top of the diaphragm D. This action may occur, forexample, by the suction cups being retractable into sleeves. The suctioncups 366 are shown attached to a top diaphragm D in FIG. 44.

[0178] After the suction cups 366 are attached to the diaphragm D, thelifting carriage 350 and the nailing carriage 352 are lifted upward tothe position shown in FIGS. 45 and 46. The movement upward is caused bythe wedges 390 being driven under the wheels 392.

[0179] Once in the up position, the diaphragm D may be aligned relativeto the nailing carriage 352 so that the diaphragms may be properlypositioned on the subpurlin S. One way of aligning the diaphragm D isshown in FIGS. 47-50. In accordance with one aspect of the presentinvention, three sensors 410, 412, and 414 are provided that are alignedso that a first two of the sensors (410 and 412) are located just to oneside of the diaphragm D after it is lifted, and the third sensor 414 islocated just behind the diaphragm after it is lifted.

[0180] To properly align the diaphragm D, the diaphragm is first rotatedas is shown in FIG. 47 to the position shown in FIG. 48. At thislocation, the leading right edge of the diaphragm engages the firstsensor 410. The diaphragm D is then rotated in the opposite directionuntil the trailing right corner of the diaphragm engages the secondsensor 412.

[0181] Using the point of rotation and the amount of rotation of thediaphragm, geometry may be used to determine the orientation of thediaphragm. Using this geometry, the diaphragm D may be aligned centeredproperly underneath the lifting carriage 350. Then, to establish areference leading edge of the diaphragm, the diaphragm is moved as shownin FIG. 50 until it engages the sensor 414. Once engaged, the trailingedge of the diaphragm is known, and the leading edge may be calculatedby knowing the length of the diaphragm. The diaphragm D may also bemoved to the right in FIG. 50 to engage the sensors 410 and 412. Thismovement establishes or confirms the location of the right edge of thediaphragm.

[0182] Other methods may be used to align the diaphragm D properly,including but not limited to assuring that the diaphragm is properlyplaced on the lifting mechanism 340. However, the presently describedembodiment provides a structure and operation by which the alignment ofthe diaphragm D may be confirmed and/or properly set before thediaphragm enters the assembly station 110.

[0183] After the diaphragm D is properly aligned, it is advanced to theassembly station 110 by rotating the gear 384 and causing the liftingcarriage 350 and the nailing carriage 352 to move into the assemblystation and over the subpurlins S and the purlin P. This position isshown in FIG. 51.

[0184] The movements of the lifting carriage 350 and the nailingcarriage 352 are preferably operated by absolute feedback motors, suchas absolute feedback servo motors. As such, the location of the liftingcarriage 350 and the nailing carriage 352 and the speeds of the movementof the carriages may be easily set by the computer 128, and altered by aprogrammer or operator via the computer 128. Because the width of thepurlin is known, the diaphragm D may be properly centered over thesubpurlins S and aligned over the brackets B on the subpurlins using theabsolute feedback motors. The wedges 390 are then driven from under thewheels 392, causing the lifting carriage 350 and the nailing carriage352 to lower, such as is shown in FIG. 52. At this lowered position, theautomatic nailers 348 are slightly spaced from the top of the diaphragmD, and the suction cups 366 still hold the diaphragm in place.

[0185] The automatic nailers 348 are then lowered to nail the firstseries of nails into the subpurlin S and purlin P. Preferably, thisfirst nailing sequence drives nails through the diaphragm D and throughthe brackets B and into the top of the purlin P. Other nails are driveninto the subpurlins S through the diaphragm D. The nails that are driventhrough the brackets B and the diaphragm D and the purlin P are used toanchor the three components of the diaphragm, subpurlin S, and purlinrelative to one another.

[0186] The position of the automatic nailers 348 in this first nailingsequence is shown in FIG. 53. Again, in this first nailing sequence, thesuction cups remain down, as is shown in FIG. 54. In this manner, thesuction cups 366 assure that the diaphragm D is held in the properposition during the first nailing sequence.

[0187] After the first nailing sequence, the suction cups are withdrawn,as is shown in FIG. 55. The suction cups 366 are shown fully withdrawnin FIG. 56. The nailing guns also slightly retract and move to the nextlocation, described further below. At this next location, the suctioncups continue to remain upward, as is shown in FIG. 56, even as theautomatic nailers 348 are lowered.

[0188] Operation of the Nailing Carriage

[0189] After the first nails have been driven into the diaphragm by theautomatic nailers 348, the automatic nailers may be indexed to nailanother series of nails. The position where the automatic nailers isindexed depends upon the number of nailers and the desired spacing ofthe nails. In one example, the nailing carriage 352 includes five rowsof nine automatic nailers each. The automatic nailers 348 in a singlerow may be spaced, for example, a foot from one another. If such anembodiment is used, after the initial nailing, the automatic nailers 348may retract (FIG. 57), and index half the distance toward the adjacentautomatic nailer's original location (e.g., 6 inches, as shown in FIG.58).

[0190] The automatic nailers 348 then drop and nail another pattern ofnails. The nailers may also move perpendicular to the subpurlins S sothat additional nails may be driven into the purlin P through thediaphragm D.

[0191] An example of the arrangement of the five rows of automaticnailers 348 is shown in FIG. 59. As can be seen, two rows (i.e., therows to the right in the figure) of the automatic nailers 348 areadjacent to one another. This space corresponds to the edge of adiaphragm D of the leading subpurlin S. At this location, the trailingedge of the adjacent diaphragm D is nailed into the leading subpurlin,as well as the forward end of the diaphragm that has just been placed.If the diaphragm just placed is the first diaphragm that has beenplaced, then the automatic nailers 348 that would nail into the trailingend of the adjacent diaphragm do not fire. The remaining rows align withthe subpurlins S.

[0192] The embodiment of the five rows of automatic nailers 348 may beused for a variety of different roof panel structures A. Differentautomatic nailers 348 fire depending upon the location along the purlin,the length of the subpurlins S and the diaphragms D, and the position ofthe nailers relative to the subpurlins, the diaphragms, and the purlin.FIG. 60 shows the relation of the position of the automatic nailers 348and the suction cups 366, and FIG. 61 shows possible zones for theautomatic nailers 348. The representation in FIG. 60 includes additionalautomatic nailers 348 that align with the purlin. These additionalautomatic nailers permit the purlin to be attached with additional nailswithout having to index the nailers perpendicularly relative to thesubpurlins. The zones represent automatic nailers 348 that may fire atthe same time. Different zones are used based upon the above-listedfactors.

[0193] In FIG. 61, fourteen different zones are shown. When thediaphragm feeder 108 is in the assembly station 110, the F zones are atthe purlin end of the assembly station 110, and the R zones are at theopposite end of the assembly station. The guns within a zone fire inunison when so instructed by the computer 128. The zones shown are butone way to separate the guns, but the particular zones shown permit awide variety of nailing patterns for different sizes of diaphragms anddifferent nailing locations on the diaphragms. As one example, for theinitial nailing of a diaphragm that is ten feet in length and eight feetwide, and which has been placed behind another diaphragm (e.g., is notthe first diaphragm on the purlin P), all of the automatic nailers 348for all of the stations would fire. However, if a diaphragm D was thefirst diaphragm to be attached to the purlin P, then the stations F1,M5, and R4 would not fire, because there would not be another, adjacentdiaphragm in which to nail.

[0194] If, on the other hand, a diaphragm D that is being attached isonly eight feet in length, then none of the R zones would fire on theinitial nailing. As the nailing carriage 352 indexes down the rows, suchas is shown in FIG. 58, then the F and M zones continue to fire asappropriate. If, however, the nailing carriage 352 indexes sideways soas to drive additional nails through the diaphragm D into the purlin P,then the stations F1 and F4 may be turned off and the other F stationsfire as the nailing carriage is indexed. A variety of other nailingcombinations may be used so as to appropriately attach the diaphragm Dto the subpurlins and purlin. As can be understood, these nailingpatterns may change according to the number of subpurlins S used, thelength of the subpurlins and the diaphragms D, the number of nailsdesired in the nailing pattern, the position of the subpurlins S anddiaphragms D relative to the purlin P, and other factors.

[0195] Operation of the Roof Panel Structure Assembly Mechanism

[0196]FIG. 62 is a flow diagram generally representing steps forautomatically producing a roof panel structure A in accordance with oneaspect of the present invention. Beginning at step 6202, a check is madeto determine whether a purlin P is in the assembly station 110. If not,step 6202 branches to step 6204 where a purlin P is inserted into theassembly station. This operation is described in more detail with thediscussion of FIG. 63. After the purlin is inserted, step 6204 branchesto step 6206, where the purlin P is indexed the appropriate amount intothe assembly station 110. This process is described with FIG. 64, below.

[0197] If a purlin is in the assembly station 110, step 6202 branches tostep 6208, where a determination is made whether the end of the purlinhas been reached. That is, a determination is made whether any moresubpurlins S or diaphragms D will be added to the purlin P. If the endhas been reached, step 6208 branches to step 6210, where the remainderof the purlin P is fed into the exit station 112. The assembled roofpanel structure A is then removed, e.g., with the forklift F (step6212). If the end of the purlin has not been reached, then step 6208branches to step 6206, where the purlin is indexed the appropriateamount (e.g., the width of one diaphragm D).

[0198] In step 6214, the subpurlins S are advanced against a purlin Pthat is in the assembly station 110. The steps for this process arediscussed with FIGS. 65 and 66, below. In step 6216, a diaphragm D isplaced over the subpurlins S and the purlin P. This step is discussedwith FIG. 67 below.

[0199] The process then proceeds to step 6218, where the diaphragm D isnailed or otherwise attached to the subpurlin S and purlin P. Thisprocess is performed by the nailing carriage 352, was described above,and is further described with FIGS. 68-73 below.

[0200] The general overview of the process is but one way to performsome of the features of the present invention, and, has been describedabove, different orders may be used, as well as different structures forperforming the functions described herein. As one nonlimiting example,the assembly station 110 may receive two diaphragms at one time forattachment by the nailing carriage 352. As another example, subpurlinsmay be added one at a time. Also, diaphragms may be placed upside down,and subpurlins may be added over the diaphragms. Other variations arewithin the scope of the present invention.

[0201] Inserting a Purlin into the Assembly Station

[0202]FIG. 63 is a flow diagram generally representing steps forinserting a purlin P into the assembly station 110 in accordance withone aspect of the present invention. Beginning in step 6302, a purlin Pis lifted onto the lifting mechanisms 132 (e.g., by the hoist 130). Thelifting mechanisms 132 then lift the purlin P or lower the purlin P tothe appropriate height, for example by rotating the shaft 156 (step6304).

[0203] In step 6306, the purlin P is fed into the assembly station 110.This may be done manually, for example by pushing the purlin P until itengages and is caught by the toothed driven roller 180.

[0204] Once the purlin P begins to enter the assembly station 110, thecomputer 128 sets the reference for the purlin to zero at step 6308. Inthis manner, using the absolute feedback servo motors that areassociated with the toothed driven roller 180 and the belt 184, theexact amount the purlin P has been advanced into the assembly station110 may be tracked. If desired, the width of the purlin P may also besensed, for example by sensing the amount that the biased idler roller182 is moved as the purlin is inserted into the assembly station 110.

[0205] At step 6310, the purlin P is indexed an appropriate amount intothe assembly station 110. This amount might be, for example, anappropriate lead for the end of the purlin P, plus the distance of onediaphragm width. After the purlin P has been indexed the appropriateamount, it is ready for attachment of the subpurlin S and diaphragm D.

[0206] Indexing the Purlin Through the Assembly Station

[0207]FIG. 64 is a flow diagram generally representing steps forindexing a purlin P through the assembly station 110 as subpurlins S anddiaphragms D are added to the purlin. Beginning at step 6402, thetoothed driven roller 180 is rotated. Simultaneous with this rotation,the belt 184 is rotated (step 6404). Also simultaneous with movement ofthe toothed driven roller 180, the conveyor 196 is advanced. Each ofthese components engages a portion of the purlin P as it is indexedthrough the assembly station 110. Preferably, their movements aresynchronized by the computer 128 so that none of the components isworking against the others.

[0208] In addition to the toothed driven roller 180, the belt 184, andthe conveyor 196, the chain 202 advances as a purlin P is advancedthrough the assembly station 110 (step 6408). It is also desired thatthe computer 128 synchronizes the advancement of the chain 202 with themovement of the other components.

[0209] Operation of the Subpurlin Feeder

[0210]FIG. 65 is a flow diagram generally representing steps for loadinga subpurlin S into the subpurlin clamping mechanisms 106 in accordancewith one aspect of the present invention. Beginning at 6502, a query ismade as to whether the subpurlin feeders 104 are loaded. This may bedone, for example, by a sensor or another suitable detection device.Alternatively, the step may be conducted by a user, e.g., via visualinspection. The step may involve determining whether any subpurlins Sare in the subpurlin feeder 104, or may involve a determination whethera certain amount of subpurlins S are within the subpurlin feeder (e.g.,6). If a determination is made that the feeder is not loaded properly,then step 6502 branches to step 6504, where the subpurlin feeder 104 isloaded. This step may be conducted automatically, or manually by anoperator.

[0211] In either event, at step 6506, a determination is made whetherthe clamping mechanism carriage 220 is in place under the feeders. Ifnot, then the process continues to loop around until the clampingmechanism carriage 220 is in place. If the clamping mechanism carriage220 is in place, then step 6506 branches to step 6508, where thepenultimate subpurlin S within the subpurlin feeders 104 is held (e.g.,by the plungers 240).

[0212] At step 6510, the bottom subpurlin S is released, e.g., by thearms 242. After the subpurlins S have been released and have droppedinto the subpurlin clamping mechanisms 106, the arms 242 are closed, andthe penultimate subpurlin is released at step 6512. The process thenloops back to step 6502.

[0213] Advancement of the Subpurlin Clamping Mechanisms

[0214]FIG. 66 is a flow diagram generally representing steps foradvancing a subpurlin S via a subpurlin clamping mechanism 106 into theassembly station 110. Beginning at step 6602, a determination is madewhether a subpurlin S is present within the subpurlin clamping mechanism106. If not, the process continually loops back until a subpurlin S ispresent. If a subpurlin S is present, then step 6602 branches to step6604, where the pinching mechanisms 270 are closed. At step 6606, thewidth of the subpurlin S is sensed or confirmed, e.g., by thesensor/counter 282.

[0215] At step 6608, the subpurlin clamping mechanisms 106 are advancedinto the assembly station 110. The front ends of the subpurlins arelifted as they approach the purlin at step 6610. As described above,this step permits the brackets B to clear the purlin P as the subpurlinS enters the assembly station. Lifting of the subpurlins S may beprovided, for example, by the inflatable bags 330.

[0216] As the subpurlins S engage the purlin P, in step 6612 the frontends of the subpurlins are lowered so that the bracket B rests on top ofthe purlin P. The subpurlins S are then pressed against the purlin P instep 6614. This step may be performed, for example, by the cylinders286. As the cylinders 286 press the subpurlin into place against thepurlin, the sensors 296 detect the stroke of the cylinders 286, so as tosense or confirm the length of the subpurlins S (step 6616).

[0217] The subpurlins S are then lowered. It is possible that thebrackets B may stick on the purlin P during this lowering process. Tohandle such a situation, the subpurlin carriage 220 may backup slightly(e.g., ¼ inch) to prevent hanging of the brackets, and then may advanceagain after the lowering. These steps may be easily added to theprogramming of the movements for the subpurlin carriage 220,particularly where an absolute feedback motor is used to direct itsmovements.

[0218] At step 6618, the process waits until a diaphragm D is attachedto the subpurlins and purlin P (i.e., the nailing process is completed).The process continually loops back until the diaphragm D is attached.Once the diaphragm D is attached, step 6618 branches to step 6620, wherethe clamping mechanism carriage 220 is withdrawn. This process mayoccur, for example, after the diaphragm D has been initially nailed withthe first nailing pattern, and while the suction cups 366 still hold thediaphragm and subpurlin S in place. Alternatively, the clampingmechanism carriage 220 may be withdrawn after all nailing has been done.In any event, as the clamping mechanism carriage 220 is withdrawn, thesupport arm 312 is extended. As described above, the support arm 312extends out at the same rate that the clamping mechanism carriage 220retracts, and thus the support arm 312 appears to be stationary duringretraction of the clamping mechanism carriage 220.

[0219] Advancing the Diaphragms Into the Assembly Station

[0220]FIG. 67 is a flow diagram generally representing steps foradvancing a diaphragm D into the assembly station 110 in accordance withone aspect of the present invention. Beginning at step 6702, thediaphragm lift 340 raises the top diaphragm D to a reference height,e.g., spaced just below the lifting carriage 350. The lifting carriage350 is then lowered at step 6704, for example, by moving the wedges 390from underneath the wheels 392.

[0221] At step 6706, the diaphragm D is grabbed by the lifting carriage350, e.g., by the suction cups 366. The lifting carriage 350 is thenraised at step 6708. Again, this may be done by driving the wedges 390under the wheels 392, or in another suitable manner. At step 6710, thediaphragm D is aligned, for example by using the sensors 410, 412, and414.

[0222] At step 6712, the diaphragm D is advanced into the assemblystation 110. This is done, for example, by rotating the gear 384 so thatit moves along the rack 386, and moves the diaphragm carriage 346 intothe assembly station 110. The diaphragm D is then lowered onto thepurlin P and subpurlins S at step 6714. This may be done, for example,by moving the wedges 390 out from under the wheels 392. At step 6716,the first series of nails is driven by the nailing carriage 352. Afterthese nails have been driven, the suction cups 366 release the diaphragmD in step 6718.

[0223] Assembly Example

[0224] An example of steps of assembly of a roof panel structure A isshown in FIGS. 68-73. As is described further below, the steps taken bythe roof panel structure assembly mechanism 100 are different dependingupon the size of the diaphragms and the location of the purlin Prelative to the assembly station 110 (i.e., how far it has beeninserted). For example, one to four subpurlin clamping mechanisms 106may be used, depending on the width of the diaphragm, and the positionof the purlin P in the assembly station 110.

[0225] An example of steps of assembly for a four-foot-wide diaphragm Dis shown in FIGS. 68-73. The subpurlins S are spaced two feet on center.Thus, for an assembled roof panel structure A, there are threesubpurlins S that engage each diaphragm D. Two of the subpurlins arealong the edges of the diaphragms D, and one subpurlin is intermediatethe two subpurlins S on the edges.

[0226] To begin assembly, two subpurlins S are inserted into the twoleading subpurlin clamping mechanisms 106, as is shown in FIG. 68. Adiaphragm D is lowered onto the two subpurlins S so that it extendshalfway over the first subpurlin and approximately two feet beyond thesecond subpurlin and over a third subpurlin clamping mechanism 106 thatdoes not include a subpurlin therein.

[0227] The automatic nailers 348 lower, as is shown in FIG. 69. Twonailing guns fire in this sequence: The inside row of automatic nailers348 at the first subpurlin S, and the automatic nailers at the secondsubpurlin. The outside row of automatic nailers 348 at the firstsubpurlin S do not fire, because there is not a diaphragm D on that sideof the first subpurlin.

[0228] The purlin P, the diaphragm D, and the assembled subpurlins S arethen indexed down so that the rear edge of the diaphragm D is alignedover the center of the first subpurlin clamping mechanism 106, as isshown in FIG. 70. The amount of the diaphragm D that is hangingrearwardly from the previously attached subpurlin S is approximately twofeet in the embodiment shown in the drawings. This amount permits theend of the diaphragm D to be flexible, so that it may bend upward. Thisflexibility is needed when the subpurlins S are raised upward at the endof their movement toward the purlin P, for example by the air bags 330.This movement upward of the subpurlins S and the resultant bending ofthe rear portion of the diaphragm are shown in FIG. 71.

[0229] After the two subpurlins S in FIG. 71 have been lowered intoposition against the purlin P, another diaphragm D is lowered againstthe top these two subpurlins and is aligned against the back of theadjacent diaphragm. This positioning of the second diaphragm is shown inFIG. 72. The automatic nailers 348 then lower and nails are driventhrough the back end of the leading diaphragm into a subpurlin in thefirst subpurlin clamping mechanism 106, and through the front edge ofthe trailing diaphragm into the same subpurlin, and also into the secondsubpurlin. The purlin P and the attached subpurlins S and diaphragms Dthen are advanced.

[0230] The process above is continued until the end of the purlin P isreached. At this point, the last diaphragm D that has been attached hasa trailing end that extends two feet beyond the last attached subpurlinS. The subpurlin feeders 104 then drop only one subpurlin S into thefirst subpurlin clamping mechanism 106. A single subpurlin S shown inthe first subpurlin clamping mechanisms 106 is shown in FIG. 73. Afterthe single subpurlin S has been inserted, the automatic nailers 348 arelowered and only the first row of guns, i.e., the outermost of the twoadjacent sets of rows fires, driving the nails in through the end of thelast diaphragm D into the single subpurlin S.

[0231] The assembled roof panel structure A is then ready for removalfrom the assembly station 110. It can be understood that the assemblyprocess will be different than described above if the diaphragm D iswider than four feet. For example, if an eight-foot-wide diaphragm isused, then all four subpurlin clamping mechanisms 106 are filled withsubpurlins S, and the diaphragm extends two feet beyond the lastsubpurlin clamping mechanism 106. Nailing guns fire according to thesubpurlins S that are present within the subpurlin clamping mechanisms106.

[0232] The roof panel structure assembly mechanism 100 of the presentinvention provides fully automated assembly of roof panel structures A.The purlins are indexed and fed using an automated system, thesubpurlins are fed into the subpurlin clamping mechanisms 106 by anautomated system and are advanced into the assembly station via anotherautomated system, and the diaphragms are advanced into the assemblystation via yet another automated system. These automated systems do notrequire user input once started. In many locations, a sensor or sensorssense or confirm the width or length of the purlin P or subpurlin S, andthe automated system aligns the subpurlins S or the diaphragm D in theappropriate location due to the sensed width or length. Many of theautomated movements of the components of the roof panel structureassembly mechanism 100 are operated by absolute feedback motors, such asabsolute feedback servo motors. As such, the location of the componentsof the subpurlin carriage and the speeds of the operation may be easilyand accurately set by the computer 128. For example, operation may bealtered automatically due to sensor or operator input. As such, the roofpanel structure assembly mechanism 100 can save many costs and muchlabor involved in normal construction of roof panel structures A.

[0233] Other variations are within the spirit of the present invention.Thus, while the invention is susceptible to various modifications andalternative constructions, a certain illustrated embodiment thereof isshown in the drawings and has been described above in detail. It shouldbe understood, however, that there is no intention to limit theinvention to the specific form or forms disclosed, but on the contrary,the intention is to cover all modifications, alternative constructions,and equivalents falling within the spirit and scope of the invention, asdefined in the appended claims.

What is claimed is:
 1. A method of assembling a roof panel structure,comprising: using a first automated system, advancing at least onesubpurlin into an assembly station and against at least one purlin; andattaching the at least one subpurlin to the at least one purlin.
 2. Themethod of claim 1, wherein the purlin is advanced into the assemblystation by a second automated system.
 3. The method of claim 2, furthercomprising: advancing at least one diaphragm into the assembly stationand against the at least one subpurlin and the at least one purlin; andattaching the at least one diaphragm to the at least one subpurlin andthe at least one purlin.
 4. The method of claim 3, wherein the diaphragmis advanced into the assembly station by a third automated system. 5.The method of claim 1, further comprising: advancing at least onediaphragm into the assembly station and against the at least onesubpurlin and the at least one purlin; and attaching the at least onediaphragm to the at least one subpurlin and the at least one purlin. 6.The method of claim 5, wherein the diaphragm is advanced into theassembly station by a second automated system.
 7. The method of claim 5,further comprising, after attaching the at least one subpurlin to the atleast one purlin: indexing the at least one purlin through the assemblystation; advancing an additional at least one subpurlin against theadvanced at least one purlin; and attaching the additional at least onesubpurlin to the advanced at least one purlin.
 8. The method of claim 7,further comprising: advancing an additional at least one diaphragmagainst the additional at least one subpurlin; and attaching theadditional at least one diaphragm to the additional at least onesubpurlin.
 9. The method of claim 1, wherein the first automated systemcomprises a carriage for advancing the at least one subpurlin into theassembly station.
 10. The method of claim 9, wherein the at least onesubpurlin comprises a bracket for attaching to the purlin, and furthercomprising lifting at least a bracket end of the subpurlin prior toadvancing the at least one subpurlin against the at least one purlin.11. The method of claim 10, further comprising lowering the bracket endas the subpurlin is advanced against the purlin.
 12. The method of claim9, further comprising, prior to advancing the at least one subpurlininto the assembly station, automatically feeding the at least onesubpurlin onto the carriage.
 13. The method of claim 1, wherein the atleast one subpurlin comprises a bracket for attaching to the purlin, andfurther comprising lifting at least a bracket end of the subpurlin priorto advancing the at least one subpurlin against the at least one purlin.14. The method of claim 1, further comprising lowering the bracket endas the subpurlin is advanced against the purlin.
 15. The method of claim1, further comprising sensing the width of the at least one subpurlin.16. The method of claim 1, further comprising sensing the length of theat least one subpurlin.
 17. The method of claim 1, further comprisingadjusting the height of the at least one purlin prior to advancing theat least one subpurlin into the assembly station.
 18. The method ofclaim 1, further comprising, after attaching the at least one subpurlinto the at least one purlin: indexing the at least one purlin through theassembly station; advancing an additional at least one subpurlin againstthe advanced at least one purlin; and attaching the additional at leastone subpurlin to the advanced at least one purlin.
 19. A method ofassembling a roof panel structure, comprising: using a first automatedsystem, advancing at least one purlin into an assembly station;advancing at least one subpurlin against the at least one purlin in theassembly station; and attaching the at least one subpurlin to the atleast one purlin.
 20. The method of claim 19, further comprising:advancing at least one diaphragm into the assembly station and againstthe at least one subpurlin and the at least one purlin; and attachingthe at least one diaphragm to the at least one subpurlin and the atleast one purlin.
 21. The method of claim 20, wherein the diaphragm isadvanced into the assembly station by a second automated system.
 22. Themethod of claim 19, further comprising, after attaching the at least onesubpurlin to the at least one purlin: using the first automated system,indexing the at least one purlin through the assembly station; advancingan additional at least one subpurlin against the advanced at least onepurlin; and attaching the additional at least one subpurlin to theadvanced at least one purlin.
 23. The method of claim 22, furthercomprising: advancing an additional at least one diaphragm against theadditional at least one subpurlin; and attaching the additional at leastone diaphragm to the additional at least one subpurlin.
 24. The methodof claim 19, further comprising adjusting the height of the at least onepurlin prior to advancing the at least one subpurlin into the assemblystation.
 25. A method of assembling a roof panel structure, comprising:using a first automated system, advancing at least one subpurlin into anassembly station; uniting the at least one subpurlin and at least onediaphragm in the assembly station; and attaching the at least onesubpurlin to the at least one diaphragm.
 26. The method of claim 25,wherein the diaphragm is advanced into the assembly station by a secondautomated system.
 27. The method of claim 25, wherein the firstautomated system comprises a carriage for advancing the at least onesubpurlin into the assembly station.
 28. The method of claim 27, furthercomprising, prior to advancing the at least one subpurlin into theassembly station, automatically feeding the at least one subpurlin ontothe carriage.
 29. The method of claim 25, further comprising sensing thewidth of the at least one subpurlin.
 30. The method of claim 25, furthercomprising sensing the length of the at least one subpurlin.
 31. Amethod of assembling a roof panel structure, comprising: using a firstautomated system, advancing at least one diaphragm into an assemblystation and against at least one subpurlin; and attaching the at leastone diaphragm to the at least one subpurlin.
 32. The method of claim 31,wherein the subpurlin is advanced into the assembly station by a secondautomated system.
 33. The method of claim 31, further comprising sensingthe alignment of the at least one diaphragm prior to advancing at leastone diaphragm into an assembly station.
 34. The method of claim 33,further comprising altering the alignment of the at least one diaphragmresponsive to the sensing.
 35. The method of claim 34, furthercomprising using a second automated system, automatically attaching theat least one diaphragm to the at least one subpurlin.
 36. A method ofassembling a roof panel structure, comprising: using a first automatedsystem, advancing a purlin into an assembly station; using a secondautomated system, advancing at least one subpurlin into the assemblystation and against the purlin; using a third automated system,advancing at least one diaphragm into the assembly station and againstthe at least one subpurlin and the at least one purlin; and attachingthe at least one diaphragm to the at least one subpurlin and the purlin.37. The method of claim 36, further comprising a fourth automated systemfor automatically attaching the diaphragm to the at least one subpurlinand the purlin.
 38. The method of claim 36, further comprising, afterattaching the at least one diaphragm to the at least one subpurlin andthe purlin: using the first automated system, indexing the purlinthrough the assembly station; using the second automated system,advancing an additional at least one subpurlin against the advancedpurlin; using the third automated system, advancing an additional atleast one diaphragm into the assembly station and against the at leastone subpurlin and the advanced purlin; and attaching the additional atleast one subpurlin and the additional at least one diaphragm to theadvanced purlin.